X-ray tube.



J. ROSENTHAL.

' X-RAY TUBE.

APPLICATION FILED SEPT. 21, 1906.

1,028,969. Patented Ju ne 11,1912.

UNITED AT PA NTo FIoE.

I JOSEPH ROSEN THAL, 0F MUNICH, GERMANY.

x naY TUBE.

Specification of Letters Patent. Patented J n ne 11, 1912,.

Application filed September 21, 1905. Serial No. 279,423.

To all whom it may concern:

Be it known that I, Josnrn ROSENTHAL, engineer, citizen of Germany,residing at Munich, Bavaria, Germany, have invented certain new anduseful Improvements in X-Ray Tubes; and I do hereby declare thefollowing to be a full, clear, and exact description of the invention,suchas will en-v able others skilled in the art to whichit ap pertainsto make and use the same.

This invention comprises improvements in or relating to Rontgen-raytubes.

It is known that the Rontgen-rays emitted by ordinary Rontgen-tubes arenot homogeneous, and that they comprise rays which vary to.a very greatextent in penetrative power. 1

The object of the present invention is to provide a Rtintgen-t'ube bymeans of which mixtures of Riintgen-rays, in which rays of highpenetrative power predominate, are obtained. For this purpose-a screenmay be arranged inside the tube, about the anticathode, consisting ofmaterial which is penetrated by the rays of higher penetrative power,but by which the rays of lower penetrative power are absorbed, saidmaterial being, for instance, sheet-iron, porcelain, or the like.

The drawing shows a section of one form of a Rontgen-tube embodying myinvention.

Referring to the drawings, a is the cathode, b the anti-cathode, and 0a,cylindrical screen, for example, of sheet-iron, mounted on andsurrounding said anti-cathode.

It will benoted that the rays emanating from the. anti-cathode aredirected against the walls of the cylindrical screen, whereby the raysof lower penetrative power are ab sorbed, while those of higherpenetrative power pass outward, thus giving a more nearly homogeneousradiation,

Having thus fully described my invention, what I claim is 1. ha Rontgenapparatus, the combina-v tion, with the Rontgen tube, the cathode andthe anticathode, of means arranged within said tube to permit the raysto pass directly from the cathode to the anticathode but to prevent theemanation of rays direct from the anticathode against the walls of thetube.

2. In a Rontgen apparatus, the combination, with the Rontgen tube,thecathode and the anti-cathode, of a screen arranged with-- in said tubeand surrounding the anticathode to permit the rays to pass directly.from the cathode to the anticathode but to intercept all rays emanatingdirectly there-- from. v 1

I 3. In a Rontgen apparatus, the combination, with the tube, the cathodeand the anticathode, of a screen mounted on the anticathode andsurrounding the same to permit the rays to pass directly from thecathode to the anticathode but to intercept" the rays emanating from theanti-cathode.

4. In a Rontgen apparatus, the combination, with the tube,-the cathode,and the anticathode, of a cylindrical casing surrounding the anticathodeand having an open end directed toward ,the cathode, the casingpermitting the rays from the cathode to pass through its open enddirectly to the anticathode but acting to filter the rays emanatingdirectly from the anticathode.

5. An X-ray tube having a massive target of material substantiallyimpervious to X- rays and provided with a deep recess to receive thecathode stream entering said target, a cathode mounted in said tube tocooperate with said target, said tube being formed of a glass bodysurrounding said target and cathode, interceptors formed on said targetto minimize the discharge of undesirable radiation therefrom and awindow substantially transparent to X-rays mounted on said targetthroughwhich the X-rays pass before striking'the body of said tube.

6. An X-ray tube having a massive target of materialsubstantiallylmpervious to X- rays and provided with a deep recess to receive thecathode stream entering said tar get, a cathode mounted within said tubeto cooperate with said target, interceptingmeans on said target tointercept undesirable radiation therefrom and a window substantiallytransparent to X-rays and impervious to undesirable radiation mountedwithin saidtube in the path of the useful X-rays before they strike thebody of said tube.

7. An X-ray tube having a target, a cathode mounted within said tube tocooperate with said target, intercepting means mounted within said tubeto intercept undesirable radiation from said target, and a windowsubstantially transparent to X-rays mounted within said tube in the pathof the useful 1:)

